In this exercise, you’ll refactor some ES5 code into ES2015.
Given this function:
function filterOutOdds() {
var nums = Array.prototype.slice.call(arguments);
return nums.filter(function(num) {
return num % 2 === 0
});
}
JavaScript
Refactor it to use the rest operator & an arrow function:
/* Write an ES2015 Version */
JavaScript
findMin
Write a function called findMin that accepts a variable number of arguments and returns the smallest argument.
Make sure to do this using the rest and spread operator.
findMin(1,4,12,-3) // -3
findMin(1,-1) // -1
findMin(3,1) // 1
JavaScript
mergeObjects
Write a function called mergeObjects that accepts two objects and returns a new object which contains all the keys and values of the first object and second object.
mergeObjects({a:1, b:2}, {c:3, d:4}) // {a:1, b:2, c:3, d:4}
JavaScript
doubleAndReturnArgs
Write a function called doubleAndReturnArgs which accepts an array and a variable number of arguments. The function should return a new array with the original array values and all of additional arguments doubled.
doubleAndReturnArgs([1,2,3],4,4) // [1,2,3,8,8]
doubleAndReturnArgs([2],10,4) // [2, 20, 8]
JavaScript
Slice and Dice!
For this section, write the following functions using rest, spread and refactor these functions to be arrow functions!
Make sure that you are always returning a new array or object and not modifying the existing inputs.
/** remove a random element in the items array
and return a new array without that item. */
function removeRandom(items) {
}
/** Return a new array with every item in array1 and array2. */
function extend(array1, array2) {
}
/** Return a new object with all the keys and values
from obj and a new key/value pair */
function addKeyVal(obj, key, val) {
}
/** Return a new object with a key removed. */
function removeKey(obj, key) {
}
/** Combine two objects and return a new object. */
function combine(obj1, obj2) {
}
/** Return a new object with a modified key and value. */
function update(obj, key, val) {
}
JavaScript